Extend the Hypperlink dialog and add "rel" attribute to the options, so that it can be edited. This is quite important for security reasons if you use "target=_blank"
https://www.jitbit.com/alexblog/256-targetblank---the-most-underestimated-vulnerability-ever/
https://blog.dareboost.com/en/2017/03/target-blank-links-rel-noopener-performance-security/